Yarn



Patented June 6, 1944 YARN Ernest 0. Geier and Rudolph Er Semmler, NewYork, N. Y.

Application July 16, 1943, Serial No. 494,946

4 Claims. -('Cl. 57-139) This invention relates to yarns and fabrics andmethods of manufacturing the same.

The present application is a continuation in part of our copendingUnited States patent application, Serial No. 468,986, flied December 14,1942, relating to heat resisting materials.

This patent application describes yarns, and fabrics which have a greatresistance to heat and which are composed of threads of glass combinedwith'asbestos threads.

It was found that the combination of glass threads with asbestos threadsproduces yarns and fabrics which have excellent heat resistingproperties and are suitable for various purposes which cannot beattained with ordinary textile fabrics or fabrics consisting solely ofglass or asbestos.

Practical experience has shown that the combination of glass threads andasbestos threads into a single heat resisting yarn presents considerabledifllculties.

Glass threads are provided with smooth surfaces and asbestos threadsstrip back or slide off these smooth surfaces, withthe result that thethreads are separated and the uniformity of the yarn cannot be attained.

An object of the present invention is the provision of a methodofcombining glass threads and asbestos threads into a single yarn whichwill be compact and uniform in composition and which may be convenientlyused for weaving heat resisting fabrics.

Another object is the provision of heat resisting fabrics having greatflexing capacities and great tensile strength composed of uniform yarnsconsisting of glass and asbestos threads.

A further object is the provision of a yarn which is so formed ofasbestos and glass threads that the advantageous properties of thesematerials are combined in the best possible manner.

Other objects of the present invention will become apparent in thecourse of the following specification.

It is a matter of general knowledge that asbestos yarns and fabrics donot possess sufilcient strength when used as dust collectors and may bedamaged by metallic oxide deposits and the like. Glass threads, whilebeing suiliciently strong, are not flexible to the required extent andbreak when flexed.

A combination of glass and asbestos into a single yarn may in certaininstances compensate for the above described drawbacks of the individualthreads, although certain combinations of these threads were found to beentirely inadequate for weaving purposes.

Numerous experiments carried out with a very large number of glass andasbestos threads in a large variety of combinations, showed that theadvantageous qualities of asbestos and glass can be brought out in asingle yarn only if the throwing or twisting of the glass and asbestosthreads is carried out in a specific manner.

In accordance with the present invention, the sliding of asbestosthreads is eliminated, and a yarn having excellent heat resisting andflexing properties is produced, provided that such yarn is formed of twothreads of asbestos or glass which are twisted together a somewhatgreater number of turns than a subsequent twisting which is carried outafter the addition of a third thread.

The preferred twisting ratio was found to be seven turns of two threadsin one direction, and five turns of three threads in the oppositedirection.

It was found that when asbestos and glass threads are twisted or thrownin this manner, the sliding of asbestos in relation to glass iseliminated entirely, and a very strong yarn is produced which has greatheat resistance and a great flexing capacity as well as a very hightensile strength.

The invention will appear more clearly from the following detaileddescription when taken in connection with the accompanying drawingshowing by way of example, preferred embodiments of the inventive idea.

Inthe drawing:

Figure 1 illustrates diagrammatically a yarn made in accordance with theprinciples of the present invention.

Figure 2 is a diagram illustrating a fabric composed in part of yarnsillustrated in Figure 1.

Figure 3 is a diagram illustrating a six shaft satin fabric the fillingof which is composed of the yarn illustrated in Figure 1.

Figure 4 is a diagram illustrating a fabric composed solely of yarnsillustrated in Figure 1.

Figure 1 shows a yam which consists of three threads 3a, 4a, and 5.

The threads 3a, and 4a, are composed preferably of the same materialalthough they may consist of different materials. Consequently, thethreads 3a, and la may consist of fiber glass, or asbestos, or thethread 30 may consist'of asbestos, while the thread la may be made ofglass.

It is advantageous to provide the threads 3a and 4a with a preliminarytwist before they are twisted together.

In the example illustrated, each of the threads 3a and 4a consist offiber glass, size 225 1/0. Each of these threads has an initial twist of1.6 turn Z. Obviously, this initial twist may be carried out in theopposite direction.

The two threads 3a and la are twisted seven turns 8 and then a thirdthread 5 is added to the two threads.

The thread 5 may consist of asbestos, size 3510 and is provided with aninitial twist 15 turns Z. Thereupon, all three threads, la, la, and 5are twisted or plied five turns 2 twist.

It is apparent that the above described yarn which isillustrated inFigure 1, has been given solely by way of example and that the turns maybe varied within certain limits.

For instance, the first two threads in and in may be plied with a Ztwist and then three threads may be plied with an 8 twist.

It is even possible to use the same type of twist, namely, 8 or z, fortwo threads as well as for three threads, although experience has shownthat opposite twists produce the best 1esults.

While the number of turns may be varied, experience has shown that thebest possible results are attained when the twisting of the two threads.consists of seven turns while the twisting of three threads consists offive turns. The yarn having these twists is easy to manufacture and thetwists set permanently in such a manner, that the curling of the yarnand the opening-up of the threads are avoided.

While this proportion may be changed, it was found to be essential thatthe twisting of the two threads have a larger number of turns than thetwisting of three threads, in order to avoid the slipping of asbestosupon glass yarn.

It is possible to vary the number of threads used in the combinationyarn to adapt it to certain specific purposes. For example, six ends offiber glass and two ends of asbestos yarn were found to be most suitablefor special purposes.

The number of plies can be varied as well. For example, a combination ofthree yarns, each consisting of three ends of fiber glass and one end ofasbestos yarn, can be plied together, and three yarns thus produced canbe plied together again "to produce a heavy cord.

In this manner, by varying the number of individual ends, the number ofplies, the number of turns inserted, as well as the chosen direction ofthe twist, many combinations of threads of asbestos yarn and fiber glasscan be obtained within the scope of the present invention.

The yarn manufactured in the described manner and consisting of aplurality of threads, at least one of which is asbestos while at leastone other is glass, may be conveniently woven or knitted into fabricswhich are exceptionally well suited for a variety of industrialpurposes.

Experience has shown that an excellent fabric is produced when thefilling consists of the described yarn 6, while the warp consists offiber glass 1. This fabric is illustrated in Figure 2.

However, the warp of a woven fabric may be made of asbestos threads orthe described yarn 6, while the filling may also consist of glassthreads or asbestos threads.

Figure 3 illustrates a six shaft satin fabric, the filling of which iscomposed of the combination yarn 6, while the warp consists of fiberglass 1.

Combination yarn 6 is predominently located upon one side of thisfabric, while fiber glass I is exposed upon the other side.

It is also possible to prodce a fabric consisting solely of thecombination yarn 6, as shown in Figure 4 of the drawing.

All of such fabrics have the advantageous properties of extremely highheat resistance and tensile strength and a great capacity of flexing. Aparticular advantage of the combination yarn 8 is that it absorbseasily, varnishes, resins and other chemicals. Furthermore, the fabricscomposed of these yarns can be used as a base for laminated plasticshaving a high heat resistance.

The described fabrics are most advantageously employed in the aviationindustry, for instance, as boots over landing gears, or in chambers ofairplane guns, on ships as pipe laggings, in the electrical industry asinsulators, and for a variety of other purposes. I

It was found that a 'fabric consisting solely of the combination yarn 6will satisfy most requirements but that great tensile strength isattained without sacrificing the faculty of hi h heat resistance whenthe warp is made of fi er glass. However, for some other purposes, beter results may be attained if different combinations of the yarn 6 withglass and asbestos threads are utilized.

In general, it is apparent that the examples shown above are givensolely by way of illustration and not by way of limitation and thattheabove described invention is subject to wide variations andmodifications within the scope of the appended claims. All of suchvariations and modifications are to be included within the scope of thepresent invention.

What is claimed is:

1. A yarn consisting of at least three threads, at least one beinga-glass thread, at leastone other being an asbestos thread, at least twoof said threads being identical threads, said identical threads beingtwisted around one another in a single direction, said twisted identicalthreads and said remaining thread or threads being twisted around oneanother in the opposite direction, the number of turns in the firstdirection and the number of turns in the second direction being in theratio of 7 to 5.,

2. A yarn consisting of at least three threads, at least one being aglass thread, at least one other being an asbestos thread, at least twothreads being identical threads, all of said threads being individuallytwisted threads, said identical threads being additionally twistedaround one another in a single direction, said additionally twistedthreads and said remaining thread or threads being finally twistedaround one another in the opposite direction, the number of turns in theadditionally twisted threads and the number of turns in the finallytwisted threads being in the ratio of 7 to 5.

3. A yarn consisting of at least three threads, at least two beinginitially twisted glass threads and at least one thread being aninitially twisted asbestos thread, said glass threads being additionallytwisted around one another 7 turns per inch in any one direction andsaid asbestos thread and said additionally twisted glass threads beingfinally twisted around one another 5 turns per inch in the oppositedirection 4. A yarn consisting of at least'three threads,-

at least two being an initially twisted bestos threads, and at least onethread being an 'tially twisted glass thread, said asbestos thread beingadditionally twisted around one another turns per inch in any onedirection, and said glass thread and said additionally twisted asbestosthreads being finally twisted around one another 5 turns per inch in theopposite direction.

ERNEST C. GEIER. RUDOLPH E. SEMZMLER.

